Title

The AIX SSH daemon must not allow compression. (Cat II impact)

Discussion

If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection, potentially with root privileges.

Check Content

Check the SSH daemon configuration for the Compression setting by running: # grep -i Compression /etc/ssh/sshd_config | grep -v '^#' Compression no If the setting is not present, or it is not set to "no", this is a finding.

Fix Text

Edit the "/etc/ssh/sshd_config" file and add (or modify) the following line: Compression no Restart the SSH daemon: # stopsrc -s sshd # startsrc -s sshd

Additional Identifiers

Rule ID: SV-215296r508663_rule

Vulnerability ID: V-215296

Group Title: SRG-OS-000480-GPOS-00227

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.